Trimmer-shifting mechanism for sewing-machines.



1. M. MERROW. TRIMMER SHIFTING MECHANISMFOR SEWING MACHINES.

APPLICATION FiLED APR. 7. 1913.

Patented Dec. 5,1916.

2 SHEETSSHEET1 |NvENTOP W wawem WITNESSES HIS TTORNEYS.

1. MI MERROW.

TRIMMER SHIFTING MEQHANISM FOR SEWING MACHINES. APPLICATION FILED APR. 7,:9l3.

1207;063. Patented Dec. 5,1916.

2 SHEETS-SHEET 2.

WITNESSES- INVENTOR BY-MW i HIS ATTORNEYS.

' i snares PAENT rrrea.

JOSEPH M. MERROW, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE MEIR-ROW MACHINE COMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF CON- NECTICUT.

TRIMMER-SHIFTING MECHANISM SEWING-MACHINES.

To all whom it may concern:

Be it known that I, JOSEPH M. Mnmzow, a citizen of the United States, residing at Hartford, county of Hartford, State of Connecticut, have invented certain new and useful Improvements in 'lrinnner-Shifting Mechanism for Sewing-Machines; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this specification, and to the characters of reference thereon.

My invention relates to trimming mechanisms of sewing machines.

An object of the invention is to provide mechanism for shifting the trimming cutters laterally and consequently varying the width of trimming either while the machine is in operation or while at rest.

A further object is to provide means for locating desired intermediate positions between the extremes of trimming; and a still further object is to provide a mechanism of this class applicable to the Morrow type of trimming and oi erseaming machines. A machine of this type is described or referred to in Patents #798,638 and #733,760.

Vith these and other objects in view, my invention consists in certain new and useful combinations of elements and details of construction as hereinafter shown and described and pointed out more particularly in the claims.

In the drawings: Figure l is a front elevation of a Merrow trimming and overseaming machine of the type above mentioned to which an embodiment of my invention has been applied, with part of the frame of the machine broken away and parts of the machine removed to disclose internal mechanism, and having the work plate and the needle plate support shown in section on the line ll of Fig. 2. Fig. 2 is a left end elevation, partly in section, of the machine shown in Fig. '1, the frame being cut away on the line 22 of Fig. 4. Fig.3 is a right hand view of the machine. Fig. 4 is an elevation of the back of the machine with parts removed. Fig. 5 is a transverse sectional View of the shifting cam and its supporting bracket on the line 55 of Fig. 41. Fig. 6 is'a detached view of some of the parts of the shifting mechanism, showing them in their relative positions.

Specification of Letters Patent.

Application filed April 7, 1913. Serial- No. 759,456.

Patented new, 1916.

Like characters of reference indicate like parts throughout the drawings.

The stitch-forming mechanism of the machine shown in the drawings, to which the present embodiment of my invention has been applied is of the usual form: 20 indicating the presser foot, 21 the feed dog, 18 the needle, 15 the lower looper, 16 the upper looper, 19 the needle plate and 17 the work plate.

In the embodiment of my invention illustrated, 22 denotes the upper vibrating triming cutter, 29 a carriage to which the cutter is secured by the clamp 30 and its screw 31. The carriage 29 is secured to the carrier or yoke lever 21 which is fulcrumed at its end 24, (as will hereinafter be more fully described), and the yoke portion 21 of which is so mounted on an eccentric 1 1 and its embracing block 14 that the block is free to have longitudinal movements with relation to the carrier, and the carrier is free to move transversely with relation to the block. The rotation of the eccentric 14 which is preferably formed on the cam 14 causes the vibration of the carrier 24 and thus imparts cutting movements to the cutter 22. The cam 14 is mounted on the shaft 141 which has bearings at each end in the frame 10 and the said cam has gear connection with the cam 12* as shown by the numerals 12 and 141*, the dotted lines in Fig. 1 representing the face and the dot and dash lines in Fig. 2 representing the pitch lines of the gears. The cam 12 is mounted on the shaft 12 which is driven by the pulley 13.

The end 24-. of the carrier 2 1. which is fulcrumed on the rock shaft 50, is fixedly secured near one end thereof by the set screw 26 the point of which engages the spot 50. This end of the rock shaft has bearings in the cap 25, which is secured to the frame 10 and which is recessed (as shown in Figs. 2 and 4) to receive the end 2 1 of the carrier and both allow the said carrier to vibrate and permit of its lateral movement, of which movement more will be said. An elongated hole 25 is made in the cap to give access to the screw 26.

On the end 50 of the rock shaft 50. is formed a head or flange 50 having a bearing face 50 and a shoulder 50. The face 50 is held in operative engagement with the face 53 on one end of the shifting cam and 51 forms the shoulder 51 the angu,

larity of which with respect to the axis of the said bores should correspond to the angularity of the shoulder 50 with respect to the axis of the rock shaft. The collar 51 is held in fixed relation to the portion 53 of the shifting cam by means of the set screw 52 the point of which enters the spot 53 formed on this portion of the cam. The flange 50 is allowed sufficient clearance in the bore 51 and between the surfaces 53 and 51 for a running fit and oil hole 51 is provided for lubricating these surfaces. The collar 51, the flanged end 50 of the rock shaft and the portion 53 of the shifting cam when thus assembled, form a sort of swivel coupling which holds the rock shaft and the shifting cam axially parallel so that longitudinally the shaft and cam move together in effect as an integral shaft, but either one may rotate or oscillate independently of the other, the faces 50 and 53 of the rock shaft and of the cam respectively forming a bearing to resist a thrust effect, and the shoulder 50 of the flange 50 and the face of the shoulder 51. form the bearing to prevent the shaft 50 and the cam 53 from being separated. Thus longitudinal movement of either will be positively communicated to the other.

Into the periphery of the body 53 of the shifting cam is cut a short spiral groove 53; this groove is engaged by the end 5% of the screw 54 which is held in its adjusted position by the check screw 55, both of these screws being threaded into a boss 56 of the cam supporting bracket 56 that envelops the body 53 of the shifting cam; the said bracket being securely held to the frame 10 by the screws 57. In a boss 56 of this same bracket, is threaded a screw 64. adjust-ably supporting a spring 63 which surrounds the shank 62 of the shoe 62 and forces the face 62 of the said shoe against the periphery of the body 53 of the shifter cam thus acting as a brake and tending to keep the said cam in its adjusted position.

The hub 60 of the shifting lever 60 is secured to the portion 53 of the shifting cam by means of the set screw 61 threaded into the boss 60 of the shifting lever. This lever in addition to the free arm 60 which is adjustable by the operator, has an arm 60 in which is a bore 60 the outer end of which terminates in a slot 60 In this bore and slot works a pawl 65 having a head terminating in a pointed or V shaped end 65 and having a shank 65 surrounded by a spring 66, which spring tends to force the sald pawl outward. This pawl cooperates with one or more notches in a stop plate 67 which is preferably curved on a radius equal to the distance at which it is placed from the axis on which the pawl 65 swings. The said stop plate is adjustably secured to the portion 56 of the cam supporting bracket by the screws 68 passing through the slots 67. The pawl and notches, cooperating with the brake serve to locate and maintain the cutters in a desired position. For limiting the extreme positions of the lever 60 and consequently the cutters, (as hereinafter explained) the stop pins 69 and 69 are provided.

The lower cutter 23 is secured by means of the clamp lO and its nut 40 to the carriage 3a, which slides in guideways in the support 33, the guideways being provided with the gib 36 which is adjusted by means of the screw 37 and the adjustment maintained by the check nut 38. The cutter 23 is yieldingly pressed toward and kept in contact with the cutter 22 by the spring 72 in the bore 33, which spring operates through the lever 7 0 in the recess 33 and which lever is fulcrumed on the pin 71 and bears with its end 70 upon the outer end of the carriage 34 (as best seen in Figs. 1 and 4t). The spring 7 2 thus causes the carriage and its cutter 23 to follow the movements that are imparted to the cutter 22. The pressure of the spring 72 is adjustable by means of th screw 73 threaded into the support 33.

In the operation of my device when a maximum width of trimming is desired the lever 60 is raised until the arm 60 strikes the stop pin 69 thus preventing further movement; if a minimum width of trimming is desired the lever 60 is lowered as shown in the dotted lines in Fig. 3 until stopped by the collision of the arm 60 with the stop pin 69'. If an intermediate variation in the width of trimming is desired, the notches 67 and the pawl 65 are brought into use, the lever 60 being moved until the pawl falls into the desired notch which will locate a desired width repeatedly and keep the shifting lever in position until moved by the hand of the operator.

For varying the position of the limits.

of the range of adjustment efiected by the lever 60 and the cam 53, the cutter 22 has the usual adjustment with relation to the carrier 2% by means of the carriage 29, the clamp 27 and its screw 28. If it is desired to vary the position of the intermediate points as located by the notches, the stop plate 67 may obviously be adjusted to the desired position.

The manipulation of the lever 60 effects the lateral movement or adjustment of the cutters in the following manner: When the lever 60 is raised from the position shown in the dotted lines in Fig. 3, the cam 53 turns, from the position in which it is shown in Fig. 6, in the direction of the arrow in the said figure and passes toward or through the position shown in Figs. f and 5 until the lever is stopped either voluntarily or by the stop pin 69, and b virtue of the portion 54: of the screw 54: which is rigidly held by the bracket 56) entering and engaging the spiral groove 53*, the cam is caused to move bodily toward the position shown in the dotted lines in Fig. 6. This longitudinal movement but not the rotary movement is transmitted to the rock shaft 50 through the swivel coupling (formed by the collar 51 and the flange 50 in a positive manner, which in turn moves the carrier 24: laterally, (see the dotted lines in Fig. 6), sliding the yoke portion 24: on the eccentri block 14: and causing the cutter 22 which is mounted thereon to move with it. The cutter 23, being pressed by the spring 72 toward and against the upper cutter 22, follows the movement of this cutter. Lowering the lever 60, conversely moves the cam in the opposite direction thrusting the rock shaft 50, the carrier 24 and the cutter 22 ahead of it and causing the cutter 23 to be forced back against the yielding pressure of the spring 72.

Owing to the swivel coupling above mentioned, the oscillation of the rock shaft 50, due to the vibration of the carrier 24: which is mounted thereon, does not affect or alter the position of the shifting cam 53 while the machine is in operation, and it will be further noted that the tendency of the friction, arising from the oscillation of the rock shaft in the swivel coupling, combined with the tendency of the spring 72 to move the shifting cam is overcome by the action of the brake 62, and the pawl 65 and stop plate 67. Thus, in the manner above explained, the width of trimming and also the width of seaming may be varied either while the machine is in operation or when at rest, by moving the free end of the lever 60 and an adjustment thus secured will be maintained.

l/Vhile I have described the devices shown with much detail it is obvious that my invention is not limited to the specific form or to the details of construction herein shown.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The combination, in a trimming mechanism of an operating cutter and a carrier therefor, a stationary cutter and a sliding carriage for the same, a support for the carriage, a spring and a lever to press the stationary cutter yieldingly against the operating cutter, a rock shaft upon which the said operating cutter carrier is mounted, a cam, a coupling for connecting the cam to the rock shaft, and means for partially rotating the cam whereby the operating cutter is positively shifted from side to side.

2. In a trimming and overseaming machine in combination with the trimming mechanism thereof, a moving cutter, a carrier for the same, a cor'iperating stat-ionar Y cutter yieldingly pressed against the first named cutter, a rock shaft upon which the said carrier is mounted and means, including a cam positively connected to the said rock shaft, whereby the operating cutter may be positively moved toward and away from the line of sewing.

3. In a trimming and overseaming machine in combination with the trimming mechanism thereof, an operating cutter and a carrier therefor, a stationary cutter yieldingly pressed against the first named cutter, a rock shaft upon which the said cutter carrier is mounted, and a cam positively connected to the said rock shaft whereby the operating cutter may be positively moved toward and away from the line of sewing.

4. In combination in a trimming mechanism, a pair of cutters, a carrier for one of the cutters, a rock shaft to which the said carrier is secured, a cam operatively connected with the rock shaft and means for partially rotating the cam whereby the cutter carrier and its cutter may be positively moved by the cam toward and away from the line of trimming.

5. In a machine of the class described and in combination with the trimming mechanism thereof, a pair of cooperating cutters, means for holding and supporting the cutters, shifting mechanism, such as described, for effecting the lateral adjustment thereof, a stop plate, a spring pressed pawl cooperating therewith, and means, comprising a spring pressed shoe, cooperating with the said pawl to retain the shifting mechanism in its adjusted position.

6. In a trimming and overseaming sewing machine and in combination with the trimming mechanism thereof, a shifting mechanism comprising a rock shaft, a swivel coupling, a cam secured thereto, a spiral groove in the said cam, a stud engaging the said groove, a support common to the cam and stud, a lever for operating the cam, frictional means for resisting the movement of the cam, and a pawl and a plurality of stop pins for repeatedly locating a desired position in the movement of the shifting rechanism.

7 In combination, in a mechanism of the class described, a stationary cutter, a cooperating moving cutter and a carrier therefor, a rock shaft for the carrier, a cam for shifting the rock shaft, a coupling connecting the cam to the rack shaft, the said coupling comprising a collar having an internally disposed shoulder, means for securing the said collar to an end of the shifting cam, a flange headed shaft having a face in engagement with a face of the said cam and having a shoulder in engagement with the shoulder of the said collar whereby a swivel connection is established between the said cam and rock shaft, and means for oscillating the cam manually.

' 8. In a trimming and overseaming machine, and in combination with the trimming mechanism thereof, a cutter shifting mechanism including a cam and means for controlling the movements thereof, a rock shaft, a coupling for connecting the cam to the rock shaft, the said coupling having a pair of oppositely disposed bearings arranged transversely to the axis of the cam and rock shaft, one of the said bearings being adapted to resist a thrust and the other to resist a pull, whereby the cam and rock shaft are independently free to move about their axes and whereby the longitudinal movement of the one will be positively imparted to the other.

9. In a trimming and overseaming sewing machine and in combination with the trimming mechanism thereof, a shifting mechanism comprising a rock shaft, a swivel coupling, a cam secured thereto, a spiral groove in the said cam, a stud engaging the said groove, a support common to the cam and stud, means for operating the cam, frictional means for resisting the movement of the cam and means including a plurality of stop pins for repeatedly locating a desired position in the movement of the shifting mechanism.

10. In combination in a trimming mechanism, a cutter to which utting movements are imparted and a normally statonary cutter cooperating therewith, a carriage slidably mounted in guideways provided with an adjustable gib, means for clamping the 4 normally stationary cutter to the said carriage whereby the said cutter is supported and constrained, a spring for yieldingly pressing the said normally stationary cutter into engagement with the moving cutter and 5 means for adjusting the pressure of the said spring.

11. In combination with atrimming mechanism providing a cutter to which cutting movement is imparted by an actuating 5 mechanism, comprising a cutter carriage to which the cutter is adjustably secured, a vibrating carrier for the cutter carriage on which carrier the said cutter carriage is adjustably mounted, and means for vibrating 6 the cutter carriage carrier, a mechanism wherebythe position of the line of trimming may be varied, embodying a mechanism for shifting the vibrating cutter carriage carrier positively in both directions along a line extending transversely to the direction of the line of trimming, a normally stationary cutter secured to a sliclingly mounted carriage, a spring whereby the said normally stationary cutter is yieldingly maintained in cutting engagement with the moving cutter throughout the movements and the positions of the said moving cutter, and a screw whereby the said spring may be adjusted. 7

JOSEPH M. MERROW.

Witnesses:

GEORGE ALLEN PAGE, P. T. MnRRow.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner of Patents, Washington, D. G. 

